Just to show a different approach:
 Code:
Dim $OU1, $OU2, $x
$OU1 = GetComps("OU=Computers,OU=branch1,DC=domain,DC=local")
$OU2 = GetComps("OU=Computers,OU=branch2,DC=domain,DC=local")

For Each $x in $OU1
  ;Can list this to a text file too
  ? $x
Next

For Each $x in $OU2
  ;Can list this to a text file too
  ? $x
Next

Function GetComps($strAdsPath)
  Dim $objAdsPath, $obj, $filter[0], $arrComps[]
  $filter[0] = "Computer"
  $objADsPath = GetObject("LDAP://"+$strAdsPath)
  $objAdsPath.filter = $filter
  For Each $obj in $objAdsPath
    ReDim Preserve $arrComps[UBound($arrComps)+1]
    $arrComps[UBound($arrComps)] = $obj.cn
  Next
  $GetComps = $arrComps
EndFunction


You can also then join $OU1 and $OU2 into 1 array, but I figured you would like to have them separate. But if you don't the fnLDAPQuery i the best option here. Also fnLDAPQuery is faster then this solution.